JP6015950B2 - Embankment structure with improved seismic performance of multi-tiered concrete blocks - Google Patents

Description

  The present invention is intended to prevent collapse and overturning caused by severe horizontal vibration caused by earthquakes in breakwater bodies or quay walls, quay walls, breakwaters, seawalls, etc. The present invention relates to a technique that can be prevented by using an elastic mat.

  There are structures such as breakwater, jetty, wave breakwater, breakwater, mooring berth, wharf, landing place, revetment, etc. .

  These levee bodies are designed to transmit the load by direct contact between the upper and lower concrete blocks. The contact between the concrete surfaces has a low coefficient of friction and is easily slid in the horizontal direction. The block moved horizontally and the masonry of the concrete block collapsed or fell, and the function of the levee body was lost. In addition, even if a tenon is provided to stop the relative movement over a predetermined distance between concrete blocks, the tenon is destroyed or the concrete block moves over the tenon due to vertical vibration or lifting pressure. It caused the body to collapse.

  As a countermeasure, the mass of the concrete block can be considerably eliminated, but increasing the mass has the disadvantage that the structure becomes larger and the construction cost is increased, and that a large installation area is required. there were. In addition, when the dominant frequency of seismic motion and the resonance frequency of the concrete block coincide, there is a risk that the embankment structure will collapse only by increasing the mass of the concrete block.

  Patent Document 1 below discloses a revetment structure in which a rubble mound is constructed on the seabed ground where the caisson is installed, and then the rubble mound is covered with a covering material and a flexible filler is injected into the gap between the rubble mounds. However, although the caisson is allowed to move horizontally in the present invention, the seismic resistance is not improved with respect to the dam body in which the concrete blocks are stacked in a plurality of stages only with the covering material of the rubble mound. The reason is that the bottom concrete block can be moved horizontally, but the concrete blocks stacked above it move horizontally independently with their inertia, and when the period of the earthquake is a long period, This is because the amount of horizontal movement increases and the masonry of concrete blocks collapses and collapses or falls.

Similarly, a technology that installs a bottom block for the purpose of load distribution between the rubble mound and the structure body, and adopts a combination that has high frictional resistance between the materials constituting the bottom block and the structure body above it. Is disclosed in Patent Document 2 below. This is also very effective in preventing the collapse and overturning of the levee body because the upper concrete block moves horizontally independently for the levee body in which the upper structure is composed of multiple layers of concrete blocks. There wasn't anything.
Furthermore, in order to maintain the joint of the concrete caisson during conveyance of the concrete caisson to the rubble mound, a technique of interposing a rubber plate caisson mat on the joint surface is disclosed in Patent Document 3 below.
The technology of this cited document 3 is a joint between a protective rubber plate caisson mat for transporting a concrete caisson and a concrete caisson, and a dam body in which a plurality of concrete blocks are stacked in the shore or in the sea. There is no disclosure about the purpose and structure of the earthquake resistance of interposing a concrete block between each stage, and the technology to give earthquake resistance and seismic control to a concrete block built in multiple stages There is no disclosure of specific ideas.

JP 2000-178941 A JP 2005-127091 A JP-A-11-229347

  The problem to be solved by the present invention is that, in a dam body structure in which concrete blocks are stacked in multiple stages, the horizontal movement of each concrete block is suppressed against the horizontal runoff of an earthquake, and the masonry of concrete blocks is collapsed / banked. The purpose is to effectively prevent the body from falling over with a simple additional structure, and to provide a dam body structure with high earthquake resistance and vibration control.

The configuration of the present invention that solves this problem is as follows.
1) In the dike structure with multiple layers of concrete blocks, the static friction coefficient between the load surface of the upper and lower concrete blocks and between the bottom concrete block and the ground foundation on which the concrete block is installed A rubber or plastic elastic mat with a high dynamic friction coefficient is interposed, and the engaging part that stops the movement so that the relative horizontal movement of the vertically opposed blocks does not exceed a predetermined distance is applied to the concrete block facing vertically. Provided, a static friction coefficient and a dynamic friction coefficient between the concrete block and the elastic mat are set to 1.0 or more, a shear elastic coefficient G of the elastic mat is set to 1.0 N / mm ² or more, and rubber of elastic rubber Adjust the thickness of the rubber according to the pressure receiving area of the levee body with a hardness of A50 or higher, and further calculate with the following formula A dam with improved seismic performance of a multi-layered concrete block, which controls (varies) the equivalent stiffness KB of the entire elastic mat and shifts the resonance frequency so that it does not match the dominant frequency of seismic motion. Body structure
KB = G × Ae / Σte
Here, G: Shear elastic modulus of rubber of elastic mat (KN / m ² )
: Ae: Total pressure receiving area of each elastic mat (m ² )
: Σte ... total rubber thickness of each elastic mat (m)
2) The seismic function of the multi-tiered concrete block described in 1) above, in which a rubber mat having an elastic mat shear modulus G of 1.8 N / mm ² or more is used and the equivalent rigidity KB is controlled (varied). Improved levee body structure 3) The width of a multi-tiered concrete block is a block block of 30 m or less, its mass is 1000 kg / piece or more and the number of steps is 10 or less, either 1) or 2) above Levee structure with improved seismic function of multi-tiered concrete block 4) The elastic mat used is a rubber mat, and its thickness is within 50 mm. Seismic resistance of multi-tiered concrete block according to any one of 1) to 3) above The dam body structure with improved function 5) The multi-stage concrete block according to any one of 1) to 4) above, wherein the dam body is a breakwater body provided in the sea. Levee structure with improved seismic function 6) The seismic function of the multi-layered concrete block according to any one of 1) to 4) above, wherein the dam body is a revetment with a backing material on the rear side of the land. There is a dam body structure.

  In the present invention, an elastic mat having a high static and dynamic friction coefficient is interposed between the load-loading surfaces of the upper and lower concrete blocks stacked and between the installation ground and the lowermost concrete block. Collapse of the embankment built up with the elastic mat between concrete blocks restraining horizontal movement by the static friction force or dynamic friction force and suppressing the horizontal movement amount of each concrete block against horizontal vibration caused by block earthquake Or prevent falls. In particular, since the coefficient of dynamic friction is high, horizontal movement is persistently suppressed. Also, the resonance frequency of the horizontal vibration of the levee body can be adjusted with the elastic mat by selecting the elastic body of a material with a different friction coefficient or shear elastic modulus of the elastic mat or changing the load surface area, the thickness of the elastic mat, etc. It is possible to remove the resonance frequency of the levee body from the frequency where the horizontal vibration of the earthquake is large, and the seismic resistance and the vibration control can be improved.

  In addition, the elastic mat can cushion the vertical vibrations and shocks greatly even in the vertical vibration of the earthquake. Thereby, the movement beyond the engaging part of the upper and lower concrete blocks is suppressed.

In the present invention, in particular, the static friction coefficient between the concrete blocks is about 0.5, whereas the static friction coefficient between the concrete block and the elastic mat is 1.0 or more, which greatly exceeds 0.5, and the elastic mat. The amount of movement of the concrete block is controlled by setting the shear elastic modulus G of the rubber to 1.0 N / mm ² or more, the rubber hardness of the elastic rubber to A50 or more, and controlling the value of the equivalent rigidity KB of the entire elastic mat. (Displacement) was strongly suppressed, and a stable and tenacious structure with little deviation was achieved.

  As described above, in the present invention, by setting the characteristics and dimensions of the elastic mat within the above range, the seismic energy is supplied to the concrete blocks at each stage so as to allow the horizontal movement of the upper and lower concrete blocks within a predetermined range. It absorbs the energy of the movement of the material, the deformation energy of the elastic mat and the friction energy, and absorbs it, making it possible to reduce the collapse and fall of the dam body compared to the dam body of the same mass, thus enabling downsizing of the concrete block and cost. It was supposed to be possible.

FIG. 1 is an explanatory view showing a state of masonry of concrete blocks of the breakwater body of the first embodiment. FIG. 2 is a perspective view of the first embodiment. FIG. 3 is a perspective view showing a model test state. FIG. 4 is an explanatory diagram of the vibration and measurement of the model test. FIG. 5 is a response acceleration frequency characteristic diagram of vertical and horizontal response acceleration of the fifth stage concrete block of CASE-1 in the model sweep test. FIG. 6 is a response acceleration frequency characteristic diagram of vertical and horizontal response acceleration of the fifth stage concrete block of CASE-2 in the model sweep test. FIG. 7 is a response acceleration frequency characteristic diagram of vertical and horizontal response acceleration of the fifth-stage concrete block of CASE-3 in the model sweep test. FIG. 8 is a response acceleration frequency characteristic diagram of vertical and horizontal response acceleration of the fifth-stage concrete block of CASE-4 in the model sweep test. FIG. 9 is a response acceleration frequency characteristic diagram of vertical and horizontal response acceleration of the fifth-stage concrete block of CASE-5 in the model sweep test. FIG. 10 is a response acceleration frequency characteristic diagram of vertical and horizontal response acceleration of the fifth-stage concrete block of CASE-6 in the model sweep test. FIG. 11 is an explanatory diagram of masonry showing an embodiment of the upright wave breaking block bank structure according to the present invention. FIG. 12 is a perspective view of the embodiment of FIG. FIG. 13 is an explanatory view showing an embodiment of the bank structure of the revetment according to the present invention. FIG. 14 is an explanatory view showing an embodiment of a bank structure of a revetment using the upright wave breaking block of the present invention.

The elastic mat used in the present invention is preferably an elastic body of elastic rubber (elastomer) or plastic resin of natural rubber or synthetic rubber having elasticity and a static friction coefficient and a dynamic friction coefficient of 1.0 or more, and the mass of the concrete block. Thickness with pressure resistance that can withstand is used. Since the maximum compressive stress degree of the support rubber is about 8 to 12 N / mm ² , the pressure resistance can be sufficiently ensured even when stacked in a plurality of stages.
The mass of each concrete block of the bank structure of the present invention is about several to 100 tons, and the elastic body mat is an elastic rubber mat having a thickness of 50 mm or less and can sufficiently withstand pressure resistance.
As the elastic mat, there are various types such as a hardness A69, a hardness A60, a hardness A51 equivalent to a studless tire, or a very soft one that is generally used for a fender, or a hard one that exceeds A70. However, in this invention, the thing of hardness A50 or more is used.

  As a form of interposition between the upper and lower concrete blocks of the elastic mat of the present invention, one elastic mat is fixed to the load-loading surface of one of the upper or lower concrete blocks, and the elastic mat surface is not fixed And a type having a sliding surface at the boundary between the block surface of the concrete block opposite to this and two elastic mats, the upper elastic mat is fixed to the opposite surface of the upper concrete block and the remaining The lower elastic mat is fixed to the opposing surface of the lower concrete block, and the type in which the boundary between the two elastic mats is a sliding surface, and the elastic mat is simply inserted without being fixed between the upper and lower concrete blocks. There are types. The first type is practical.

  As a method of fixing the elastic mat to the upper or lower surface of the concrete block, a method of fixing the elastic mat with a fitting such as a fitting or bolt, a method of adhering or fusing the elastic mat to the concrete block surface, or a concrete block There is a method of fixing by fitting the outer peripheral edge or small unevenness and the elastic mat.

  In addition, the concrete block of the levee body is a rectangular shape excluding the engaging part, and when the load is applied to the entire lower surface / upper surface of the upper and lower blocks, the concrete block of each step is the water reserving part / water passing part / up / down or left / right There is a case where the fitting portion has a complicated outer shape, and the load-loading surfaces of the upper and lower concrete blocks are a part of the area outside the planar shape region of the concrete block. The elastic mat is interposed on the whole or a part of these load surfaces.

  Another elastic body may be interposed between the adjacent concrete blocks on the left and right of the concrete block of the bank body. An elastic mat may or may not be interposed between the upper concrete (top plate) provided on the bank body and the uppermost concrete block. Furthermore, there is a case where a wave returning part (vertical rising part) is provided in this upper concrete and a case where it is not provided.

Example 1
Embodiment 1 of the present invention will be described below with reference to the drawings. 1 and 2 show an example of a breakwater body 1 of a breakwater in which rectangular blocks (rectangular blocks) are stacked in a staggered arrangement in five levels as concrete blocks.

The concrete blocks C1, C2, C3, C4, and C5 of each stage of the breakwater body 1 of the breakwater of Example 1 have dimensions of length 4.5 m × width 2.0 m × height 1.7 m. The mass is about 35 tons. The total mass of the five-stage concrete blocks C1, C2, C3, C4, and C5 is 175 tons, and the area of the load surface of each concrete block is about 9 m ² in total area excluding the engaging portion of the block.
In this example, elastic mats M1, M2, M3, M4, and M5 using elastic rubber with a thickness of 50 mm are interposed between the submarine foundation rubble K and the bottom concrete block C1 and between the concrete blocks in each step. is there. The elastic mat M1 is fixed to the concrete block C1 thereabove with metal fittings (not shown) and is interposed between the foundation rubble K. The dimensions of the other elastic mats M2, M3, M4 and M5 are 4.5 m × 2.0 m of the block bottom area. The upper surfaces of the elastic mats M2, M3, M4, and M5 are fixed to the concrete blocks C2, C3, C4, and C5 above them with metal fittings (not shown), and the sliding surfaces are elastic mats M2, M3, and M4. , Between the lower surface of M5 and the concrete upper surface of the concrete block below it. In the figure, H is the covering stone, J is the upper concrete, N is the root solid block, and U is the sea bottom.

  Between the upper and lower concrete blocks, as a long engaging part S (tenon) on the left and right, the fitting groove Sm having a depth of 230 mm and an upper surface width of 350 mm and a length b of about 200 mm, and a height of 200 mm and a front and rear length a and an upper surface width of 300 mm. A long fitting protrusion St is inserted. The tenon of the engaging portion S has a play of about 50 mm of the dimension (ba) in the front-rear direction.

  In the first embodiment, the elastic mats M1 to M5 can concentrate the horizontal vibration resonance points of the breakwater body 1 of the breakwater, narrow the resonance frequency band, and reduce the horizontal response force. In addition, the elastic properties and equivalent stiffness of the elastic mat have the effect of shifting the natural period of the concrete block dam body, suppressing the resonance due to the seismic dominant frequency and the natural period of the concrete block dam body at the time of the earthquake. It effectively prevents the entire body from collapsing due to sliding or falling. The resonance frequency avoids the dominant period of seismic waves generated by earthquakes. These points were generally confirmed by a model test of 1/25 scale of Example 1 described below.

(Model test)
A model test was conducted to confirm the seismic resistance and seismic control against the horizontal vibration of Example 1. The model dam body 100 was carried out on the 1/25 scale of the first embodiment.

  The state of the model test is shown in FIGS. In the figure, 100 is a model dam body, 101 is a vibrator for exciting the model dam body 100 at 1 to 100 Hz, and 101a is a vibration that horizontally reciprocates back and forth with the model dam body 100 of the vibrator. Reference numeral 101b denotes a steel protective frame of the vibration table, and 101c denotes a cylinder rod that reciprocates the vibration table 101a of the vibration exciter 101. Reference numeral 102 denotes a displacement measuring instrument for optically measuring the amount of movement in the front-rear direction of the front end faces of the concrete blocks b1, b2, b3, b4, and b5 on which the model dam body 100 is stacked, and 102a denotes the displacement measuring instrument for concrete. The arm rod 103 that is held horizontally toward the end face of the block, 103 is a horizontal response accelerometer attached to the end face of the left block, center block, right block of the uppermost concrete block b5 and a plurality of blocks in the lower stage. is there. Reference numeral 104 denotes a vertical response accelerometer that is attached to the upper surface of the uppermost (fifth) concrete block b5 and measures the vibration force in the vertical direction of the upper surface.

  The response acceleration frequency characteristic diagrams of FIGS. 5 to 10 are measured values with respect to the excitation frequency of the horizontal response accelerometer 103 and the vertical (vertical) response accelerometer 104 of the uppermost concrete block b5 of the models of CASE-1 to 6. Yes, in the figure, H-5-L is the measured value of the left block end face of the fifth stage, H-5-C is the measured value of the center block end face of the fifth stage, and H-5-R is the right side of the fifth stage block. The measured value of the block end face is shown.

The dimensions of the concrete blocks b1, b2, b3, b4, and b5 of the model test are 1/25 of the dimensions of the concrete blocks C1 to C5 of Example 1, and the volume is 180 mm in length, 80 mm in width, and 68 mm in height. Is 980000 mm ³ and has a mass of 2.25 kg. The model dam body 100 is tested without the engagement portion being provided without the engagement portion being provided. As the elastic mats m1, m2, m3, and m4, rubber mats shown in Tables 1 and 2 below were used. The thickness of the rubber mat was 2 mm.

  In the model test, the horizontal response acceleration and the vertical response acceleration were measured at three locations on the right side, the center, and the left side of the uppermost concrete block b5 for horizontal vibration with an excitation frequency of 1 to 100 Hz at 50 gal using the above model. A sweep test was performed to detect the resonant frequency.

  The models are CASE-1, CASE-2, CASE-3, CASE-4, and CASE using the rubber characteristics shown in Table 1 below as no elastic mat and elastic mats m1, m2, m3, m4, and m5. The excitation test in the low frequency range was performed separately for the cases of -5 and CASE-6.

  The model test was a decay test in addition to the sweep test. This is a damping test at the resonant frequency detected in the sweep test at 50 gal. In the simulated seismic wave test, the test was conducted at 50 gal for 10, 20, 30, 40, and 50 sec and at 300 gal for 50 sec. Furthermore, the collapse test of the displacement of the concrete blocks b1 to b5 at 6, 8, 10, 20, 30, and 40 Hz was performed.

  Cases CASE-1, -2, -3, -4, elastic mats using the characteristics of various rubber mats for the sweep test, attenuation test, simulated seismic wave test, and collapse test of these model tests The results of the test divided into cases of -5 and -6 are shown in Table 3 below.

(Resonance frequency fluctuation)
From the measurement results of the response acceleration characteristic diagrams of the sweep test shown in FIGS. 5 to 10, the resonance frequencies (frequency) of the models of CASE-1 to 6 are shown in Table 4 below.

  From this test result, the resonance frequency of the model shown in Table 4 can be varied depending on the rubber thickness of the rubber mat, the shear elastic modulus G, the static friction coefficient A, the dynamic friction coefficient B, and the equivalent stiffness KB. I found out. It has been found that by appropriately selecting the properties of the rubber mat and the value of the equivalent rigidity KB, it can be prevented from resonating with the seismic dominant frequency. The actual resonance frequency Hz of the actual levee body can be approximated to a value obtained by dividing the resonance frequency of the model by the scale ratio (25 in the present model) according to the similarity law of the model. Therefore, the resonance frequency of 30 to 60 Hz in the model test corresponds to 1 to 3 Hz of the earthquake.

  Furthermore, from FIG. 5 to FIG. 10, the average value of the response acceleration is as shown in Table 5 below. As can be seen from Table 5, the vertical response acceleration can be reduced to about ½ compared to the case without the rubber mat by the intervention of the rubber mat. Further, the horizontal response acceleration can be reduced to about 2/3 compared to the case without the rubber mat.

  In this way, in the embankment structure in which concrete blocks are built up, the initial sliding is suppressed by the static frictional force of the rubber by interposing the rubber mat. The levee body can be prevented from collapsing without jumping over.

In a dike structure in which concrete blocks are built up, the natural frequency is controlled back and forth through a rubber mat so that the structure does not resonate with seismic waves. It becomes effective by adjusting the shear elastic modulus G of rubber by making the material, rubber hardness, and rubber chemical compounding special.
The rubber equivalent rigidity KB can be controlled by changing the shear elastic modulus G, the installation area Ae, and the rubber thickness (the vibration frequency increases as the equivalent rigidity increases).
Accordingly, the equivalent rigidity KB of the rubber can be increased by increasing the shear elastic modulus G of the rubber, increasing the installation area Ae, or decreasing the rubber thickness Σte.

  For long-period waveforms observed in the 2003 Tokachi-oki Earthquake and the 2011 Tohoku-Pacific Ocean Earthquake, soft rubber is used to reduce the natural frequency by reducing the equivalent stiffness KB of the rubber. Particularly effective effects can be obtained.

  Further, as can be seen from the collapse test in Table 3, when viewed from the uppermost sliding (displacement) of the concrete block, the rubber mats A40 and A51 cause a large displacement at 10 to 20 Hz, but the rubber mats A60 and A69 exhibit the displacement. It is getting smaller. In particular, in A81, the deviation is greatly reduced and is stable at 10 Hz or less.

  Therefore, from the disintegration test in Table 3, the rubber mat has less sliding (displacement) if the rubber hardness is set to A55 or higher between CASE-3 and -4, and exceeds A69 of CASE-5 to A70 or higher. It was found that if the rigidity KB is controlled, it is close to CASE-6, the deviation is extremely small, and the stability is stable, and this is a design guideline that does not collapse.

(Other examples)
11 and 12 shows an embodiment of an upright wave-dissipating block levee body 2 installed in the sea. One stage of a block-shaped concrete block 203 having an elastic mat 202 fixed to the lower surface of a block on a foundation rubble 201 is shown. Concrete blocks 205, which are upright wave-dissipating blocks that are installed as eyes and have a water flow space thereon, are stacked in a staggered arrangement as 2, 3, 4, and 5 stages. The elastic mat 204 is fixed to the lower surface of each concrete block 205. Upper concrete 206 is installed above the uppermost concrete block 205. Between the concrete blocks 205 and between the lowermost concrete block 203 and the second-stage concrete block 205, there is provided a tenon 207 which is an engaging portion having a horizontal play of about 50 mm. As the elastic mat, the rubber mats No. 0 and No. 2 can be used. In addition, 208 is a root solid block block, 209 is a covering stone, and 210 is a sea bottom.

  The embodiment of the revetment shown in FIG. 13 is an example in which the structure of the breakwater embankment 1 of the embodiment of FIGS. 1 and 2 is used as the revetment body 3, and the embodiment of the revetment shown in FIG. 11 is an example of a bank protection wall 4 using the structure of the upright breakwater block bank 2 shown in FIGS.

  The revetment body 3 shown in FIG. 13 is formed by stacking a block of concrete blocks 315 each having an elastic mat 314 fixed on the bottom surface 311 on the bottom surface 310 of the sea bottom 310 in a five-stage staggered arrangement. A tenon 317 that is a joint is provided. In the figure, 316 is the upper concrete, 301 is the backside chestnut stone, 302 is a sandproof cloth, and 303 is the land.

  In the revetment body 4 of FIG. 14, a block-shaped concrete block 413 having an elastic mat 414 fixed on the lower surface is installed on the basic rubble 411 of the sea bottom 410, and the elastic mat 414 is fixed on the lower surface thereof. This is an example in which concrete blocks 415 that are upright wave-dissipating blocks are stacked in a four-stage staggered arrangement.

  In this example of revetment, the movement of the concrete blocks 315 and 415 to the rear is limited by the backside chestnut stones 301 and 401 and the land grounds 303 and 403, so the horizontal movement amount of the concrete block mainly to the front sea is restrained. The main thing is to do. Even in this example of the revetment, the high static friction coefficient and dynamic friction coefficient of the elastic mats 314, 414 can prevent the concrete blocks 315, 415 from collapsing and falling into the sea. In addition, it is possible to greatly limit the vibration caused by earthquakes behind the backside Kuriishi and the land.

  The present invention can be applied to buildings in which concrete blocks are stacked in multiple stages on land, in addition to underwater and underwater breakwater bodies, breakwater bodies, seawalls, seawalls, and quay walls.

1 Breakwater C1, C2, C3, C4, C5 Concrete block K Foundation rubble M1, M2, M3, M4, M5 Elastic mat S Engaging part Sm Fitting groove St Fitting protrusion J Upper concrete N Root solid block Block H Cover stone U Sea bottom 100 Model levee body b1 to b5 Model dam body concrete block m1 to m4 Elastic body mat of model dam body 101 Exciter 101a Shaking table 101b Protective frame 101c Cylinder rod 102 Displacement measuring instrument 102a Arm rod DESCRIPTION OF SYMBOLS 103 Horizontal response accelerometer 104 Vertical response accelerometer 2 Upright wave-dissipating block bank body 201 Foundation rubble 202 Elastic body mat 203 Concrete block 204 Elastic body mat 205 Concrete block which is an upright wave-dissipating block 206 Upper concrete 207 At the joint HOSO 208 Root solid block 209 Cover stone 210 Sea bottom 3, 4 Revetment wall 301, 401 Back-filled chestnut 302, 402 Sand protection cloth 303, 403 Land surface 310, 410 Sea bottom 311, 411 Foundation rubble 314, 414 Elastic body Mat 315 Block concrete block 316, 416 Upper concrete 317, 417 Hozo which is an engaging part 413 Block concrete block 415 Concrete block which is an upright wave-breaking block

Claims (6)

In the dike structure with multiple layers of concrete blocks, the static friction coefficient and dynamic friction coefficient between the load surface of the upper and lower concrete blocks and between the lowest concrete block and the ground foundation on which the concrete block is installed Both of which are provided with an elastic mat of rubber or plastic, and provided with an engaging portion for restraining the movement so that the relative horizontal movement of the vertically opposed block is not more than a predetermined distance, on the concrete block facing vertically, The static friction coefficient and the dynamic friction coefficient between the concrete block and the elastic mat are 1.0 or more, the shear elastic coefficient G of the elastic mat is 1.0 N / mm ² or more, and the rubber hardness of the elastic rubber The rubber thickness is adjusted (increase / decrease) according to the pressure receiving area of the levee body with A50 or more, and further calculated by the following formula An embankment with improved seismic performance of multi-layered concrete blocks, characterized by controlling (fluctuating) the value of equivalent stiffness KB of the entire elastic mat and shifting the resonance frequency so that it does not coincide with the dominant frequency of seismic motion Construction.
KB = G × Ae / Σte
Here, G: Shear elastic modulus of rubber of elastic mat (KN / m ² )
: Ae: Total pressure receiving area of each elastic mat (m ² )
: Σte ... total rubber thickness of each elastic mat (m) The seismic function of the multi-tiered concrete block according to claim 1 is improved by using a rubber mat having an elastic mat with a shear modulus G of 1.8 N / mm ² or more and further controlling (fluctuating) the equivalent rigidity KB. Dam body structure.   The width of the multi-stacked concrete block is a block block of 30 m or less, the mass is 1000 kg / piece or more, and the number of steps is 10 or less, improving the earthquake resistance function of the multi-stacked concrete block according to claim 1 or 2 The dam body structure.   The embankment structure which improved the seismic function of the multi-tiered concrete block according to any one of claims 1 to 3, wherein the elastic mat used is a rubber mat and the thickness thereof is within 50 mm.   The dam body structure which improved the seismic resistance function of the multi-stacked concrete block in any one of Claims 1-4 whose levee body is a breakwater body provided in the sea.   The dam body structure which improved the seismic resistance function of the multi-tiered concrete block according to any one of claims 1 to 4, wherein the dam body is a revetment provided with a backing material on a rear surface thereof.

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